The role of water quality in large mammal migratory behaviour in the Serengeti

Abstract

Surface water resources are important components of savanna landscapes, supplying large populations of wildlife with drinking water critical for thermoregulation and digestion. However, little is known about the behavioural or physiological influence of water quality on wildlife health. East African savannas are well known for their migrating populations of ungulates coinciding with seasonal and spatial patterns of forage. In the Serengeti ecosystem, seasonal rainfall, high wildlife abundance and spatially variable soil composition result in temporal and spatial differences in surface water quality. Furthermore, nutrient enrichment from dissolved minerals and animal waste transported in runoff drive bacterial and algal blooms. Previous studies have suggested that water quality may be a factor in the migratory behaviour of wildebeest as poor quality water can have significant health consequences for ungulates, including depressed milk production and reduced food conversion. This paper examines the hypothesis that water quality in the southern Serengeti plains exceeds expected maximum tolerance limits at the end of the wet season – when migratory wildlife move northward, away from this region. Data collected during the migration's movement over 3 years are examined to determine if regional differences in water quality are physiologically meaningful and how the consumption of poor quality water may influence wildebeest nutrient intake. With increased demand for surface water resources from human populations, growing climatic uncertainty and significant changes in land cover outside of protected areas, the influence of water quality on animal behaviour needs to be considered for future management strategies. Copyright © 2012 John Wiley & Sons, Ltd.

Serengeti–Masai Mara ecosystem dynamics inferred from rainfall extremes

“…The south-north and east-west spatial variations in vegetative and wet characteristics dictate migrant herbivores to move consistently with the observed variations throughout the year (Wolanski and Gereta 2001, Holdo et al 2009, Strauch 2013). In the late wet period, forage dries up, elevating surface water demand among herbivores, which raises the ecosystem competition and forces them to migrate northward to access quality water and green grasses (Strauch 2013). Moreover, the SMME wildebeests tend to avoid areas of reduced intake of green grasses along the season as the dry grasses increase enormously (Holdo et al 2009).…”

“…Along with them are zebras and gazelles forming large herds of migrating ungulates and attracting many predators (Boone et al 2006, Sinclair et al 2008. Mineral resources, vegetation and water availability dynamics principally drive the ecological migratory functioning of the SMME (Boone et al 2006, Strauch 2013. These ecosystem resources are predominantly regulated by the annual rainfall cycle across the SMME (Dobson 2009, Holdo et al 2009.…”

Effects of changes in climate and land cover on Tanzanian nature-based tourism in national parks : How are tourist attractions affected?

“…A quarter of its main tourist attraction (i.e. wildebeest migration) is triggered by rainfall (Boone et al, 2006;Musiega et al, 2006) and two-third being driven by rain-fed food availability (Mduma et al, 1999;Boone et al, 2006) and drinking water (Walonski & Gereta, 2001;Strauch, 2013). The significance of rainfall variations in Serengeti's tourism is powerful and should not be undermined.…”